

// eg [1,2,3] ->[[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
function permutation(arr){

}

// eg (10 , [2,3,4,4,5,7]) -> [2,4,4] or [3,7]
function makeChange(target , changes) {

}

